1. Field of the Invention
This invention relates to a base plate positioning mechanism in an electronic part mounting machine in which a part supplying position and a mounting position are fixed.
2. Related Background Art
Various electronic part mounting machines in which a part supplying position and a mounting position are fixed have heretofore been developed to achieve a high speed of mounting. In such electronic part mounting machines, a gear and a belt are used for a rotative driving unit for a table for positioning a base plate at a predetermined mounting position.
However, the base plate positioning mechanism according to the prior art using a gear and a belt in the rotative driving unit has suffered from the following disadvantages:
(1) In the mechanism using a gear, it is pointed out that backlash is great and noise is annoying; and
(2) In the mechanism using a belt, it is pointed out that the presence of a soft belt between a driving portion and a follower portion leads to the impossibility of rotation at a high speed and the complication of control.